Decoding compressed video data often includes inverse quantizing blocks of data comprising frequency coefficients that correspond to a region of a picture. According to certain standards, such as MPEG-2, Advanced Video Coding (AVC), and VC-9, the quantized frequency coefficients are scanned and coded using run-length codes.
Scanning is a process of placing the frequency coefficients that are most likely to be significant towards the beginning of a data structure and the frequency coefficients that are most likely to be zero toward the end of the data structure. Run length codes further reduce the amount of data required for the data structure.
Decoders often include an inverse quantizer for inverse quantizing the blocks of frequency coefficients. Block headers that are in the stream of data that include the frequency coefficients are usually processed by other portions of the video decoder. Thus, the frequency coefficients may be provided to the inverse quantizer after run-level decode without an indication of the beginning of the blocks.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.